Crystallization apparatus

Abstract

A crystallization apparatus 2, in particular for crystallizing proteins at zero gravity, comprises a crystallization cell consisting of an elastic tube 8 of which the ends can be sealed. Using a clamp means 10the tube cavity can be reversibly divided into several cells 14, 14', 14" to receive various solutions depending on the particular crystallization.

I claim: 
     
       1. An apparatus for crystallizing proteins at zero gravity, comprising: (a) a crystallization cell formed on an elastic tube having ends adapted to be sealed;   (b) said tube defining a cavity therein;   (c) clamp means having open and closed positions for reversibly dividing said cavity into a plurality of cells for receiving various solutions;   (d) said clamp means comprising a compression clamp;   (e) means for opening and closing said clamp means;   (f) first mechanical means for applying a first external pressure only to a peripheral portion of said tube;   (g) said first mechanical pressure applying means being positioned in tight engagement on a first external side portion thereof;   (h) second mechanical means for applying a second external pressure to another peripheral portion of said tube; and   (i) said second mechanical pressure applying means being positioned in tight engagement on a second external side portion of said tube lying generally opposite to said first external side portion thereof;   (j) wherein when said clamp means is switched from a closed to an open position for allowing intermixing of any solutions contained in said cells, said first external pressure applying means prevents formation of any partial vacuum in said tube to thereby prevent any gas losses.   
     
     
       2. Apparatus defined in claim 1, wherein: (a) said first mechanical means includes means for exerting a continuous pressure on the tube.   
     
     
       3. Apparatus as defined in claim 2, wherein: (a) said first mechanical means is made of an elastic material.   
     
     
       4. Apparatus defined in claim 1, wherein: (a) the compression clamp comprises mutually opposite clamping elements mounted externally thereto.   
     
     
       5. Apparatus defined by claim 4, wherein: (a) each of the clamping elements is generally wedge shaped.   
     
     
       6. Apparatus defined by claim 4, wherein: (a) the clamping elements comprise an elastic component to limit the compression.   
     
     
       7. Apparatus defined by claim 4, wherein: (a) the mutually opposite clamping elements are laterally connected together by an elastic tensioning means for facilitating opening of said cavity when said clamp means is opened.   
     
     
       8. Apparatus as defined in claim 7, wherein: (a) the elastic tensioning means is one of a cord, a tape, and a strip made of an elastic material.   
     
     
       9. Apparatus defined by claim 7, wherein: (a) the elastic tensioning means is of such a design that it will be taut and will exert a lateral pressure on the tube when the clamping means is open.   
     
     
       10. Apparatus defined in claim 1, wherein: (a) the compression clamp comprises conical clamping elements and a supporting clamping plate.   
     
     
       11. Apparatus defined in claim 1, wherein: (a) the compression clamp includes displaceable clamping elements.   
     
     
       12. Apparatus defined by claim 1, wherein: (a) several planes of samples with several zones of tubes are provided and the clamping means for all the zones and all the planes of samples can be actuated jointly.   
     
     
       13. Apparatus defined in claim 12, wherein: (a) each zone of sample tubes is provided with an individual temperature control device.   
     
     
       14. Apparatus defined by claim 1, wherein: (a) the tube is made of silicone rubber.   
     
     
       15. Apparatus defined by claim 1, wherein: (a) the elastic tube includes an integrally formed outer reinforcing bead disposed directly next to an anticipated clamping site.   
     
     
       16. Apparatus defined by claim 1, wherein: (a) the elastic tube is provided with a sleeve to be disposed directly next to an anticipated clamping site to maintain the elastic tube substantially round when said clamp means is switched from a closed to an open position.   
     
     
       17. Apparatus defined by claim 1, wherein: (a) said second mechanical means comprises a base plate comprising an array of boreholes, where elastic fastening means passing through said boreholes hold the tube securely onto the base plate.   
     
     
       18. Apparatus defined by claim 17, wherein: (a) the elastic fastening means are mounted on the tube ends and are adapted to be selectively locked into the array of boreholes of the base plate.   
     
     
       19. Apparatus defined in claim 17, and including: (a) a displaceable clamping plate having an array of boreholes disposed generally opposite to the base plate for holding the compression clamp relative to the tube; and   (b) the compression clamp includes generally pin-shaped elements for entering the array of boreholes of the base plate and the array of boreholes of the displaceable clamping plate.   
     
     
       20. Apparatus defined in claim 1, wherein: (a) the tube ends are sealed by inserting glass stoppers therein.   
     
     
       21. Apparatus defined in claim 20, wherein (a) the tubes are filled with an inert protective gas before being sealed at their ends.   
     
     
       22. Apparatus defined by claim 20, wherein: (a) one of said stoppers is generally conical in shape.   
     
     
       23. Apparatus defined by claim 1, wherein: (a) the elastic tube includes an integrally formed inner reinforcing bead disposed directly next to an anticipated clamping site.   
     
     
       24. Apparatus defined by claim 1, wherein: (a) the elastic tube includes integrally formed inner and outer reinforcing beads disposed directly next to an anticipated clamping site.   
     
     
       25. Apparatus defined by claim 1, wherein: (a) the elastic tube comprises an outer reinforcing ring disposed directly next to an anticipated clamping site.   
     
     
       26. Apparatus defined in claim 25, wherein: (a) the reinforcing ring is bonded to the tube.   
     
     
       27. Apparatus defined by claim 1, wherein: (a) the elastic tube comprises an inner reinforcing ring disposed directly next to an anticipated clamping site.   
     
     
       28. Apparatus defined by claim 1, wherein: (a) the elastic tube comprises inner and outer reinforcing rings disposed directly next to an anticipated clamping site.   
     
     
       29. Apparatus defined by claim 1, wherein: (a) the tube ends are fused shut.   
     
     
       30. An apparatus for crystallizing proteins at zero gravity, comprising: (a) a crystallization cell formed of an elastic tube having ends adapted to be sealed;   (b) said tube defining a cavity therein;   (c) clamp means having open and closed positions for reversibly dividing said cavity into a plurality of cells for receiving various solutions;   (d) said clamp means comprising a loop clamp;   (e) means for opening and closing said clamp means;   (f) first mechanical means for applying a first external pressure only to a peripheral portion of said tube;   (g) said first mechanical pressure applying means being positioned in tight engagement on a first external side portion thereof;   (h) second mechanical means for applying a second external pressure to another peripheral portion of said tube; and   (i) said second mechanical pressure applying means being positioned in tight engagement on a second external side portion of said tube lying generally opposite to said first external side portion thereof;   (j) wherein when said clamp means is switched from a closed to an open position for allowing intermixing of any solutions contained in said cells, said first external pressure applying means prevents formation of any partial vacuum in said tube to thereby prevent any gas losses.   
     
     
       31. Apparatus defined in claim 30, wherein: (a) the loop clamp comprises a sleeve inserted into a bore in a base plate for the tube through which is pulled a loop made of a yarn or wire surrounding the tube, and further comprises means for pulling tight or to loosen the loop.